3 (COOH)2 (aq) + 2 KMnO4 (aq) → 2 MnO2 (s) + 2 KOH (aq) + 6 CO2 (g) + 2 H2O (l)

This is an oxidation-reduction (redox) reaction:

2 MnVII + 6 e- → 2 MnIV (reduction)

6 CIII - 6 e- → 6 CIV (oxidation)

KMnO4 is an oxidizing agent, (COOH)2 is a reducing agent.

This is a precipitation reaction: MnO2 is the formed precipitate.

This is a gas evolution reaction, CO2 is the formed gas.

Reactants:

  • (COOH)2 – Oxalic acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Ethanedioic acid source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Wood bleach source: wikipedia, accessed: 2019-09-27, Oxalic acid dihydrate source: wikidata, accessed: 2019-09-02source: NIOSH NPG, accessed: 2019-09-02, H2ox source: wikidata, accessed: 2019-09-02
    • Appearance: White crystals source: wikipedia, accessed: 2019-09-27; Hygroscopic colourless crystals or white powder source: ICSC, accessed: 2019-09-04; Colorless, odorless powder or granular solid. [Note: The anhydrous form (COOH)2 is an odorless, white solid.] source: NIOSH NPG, accessed: 2019-09-02
  • KMnO4 – Potassium manganate(VII) source: wikipedia, accessed: 2019-09-27
    • Other names: Potassium permanganate source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Chameleon mineral source: wikipedia, accessed: 2019-09-27, Condy's crystals source: wikipedia, accessed: 2019-09-27
    • Appearance: Purplish-bronze-gray needles | magenta–rose in solution source: wikipedia, accessed: 2019-09-27; Dark purple crystals source: ICSC, accessed: 2019-09-04

Products:

  • MnO2 – Manganese oxide source: wikipedia, accessed: 2019-09-27, Manganese(IV) oxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Other names: Manganese dioxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04, Pyrolusite source: wikipedia, accessed: 2019-09-27, Hyperoxide of manganese source: wikipedia, accessed: 2019-09-27
    • Appearance: Brown-black solid source: wikipedia, accessed: 2019-09-27; Black-to-brown powder source: ICSC, accessed: 2019-09-04
  • KOH – Potassium hydroxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02
    • Other names: Caustic potash source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, Lye source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02, Potash lye source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02
    • Appearance: White solid, deliquescent source: wikipedia, accessed: 2019-09-27; White hygroscopic solid in various forms source: ICSC, accessed: 2019-09-04; Odorless, white or slightly yellow lumps, rods, flakes, sticks, or pellets. [Note: May be used as an aqueous solution.] source: NIOSH NPG, accessed: 2019-09-02
  • CO2
    • Names: Carbon dioxide source: wikipedia, accessed: 2019-09-27source: wikidata, accessed: 2019-09-02source: ICSC, accessed: 2019-09-04source: NIOSH NPG, accessed: 2019-09-02, {{plainlist| source: wikipedia, accessed: 2019-09-27, CO2 source: wikidata, accessed: 2019-09-02
    • Appearance: Colorless gas source: wikipedia, accessed: 2019-09-27; Odourless colourless compressed liquefied gas source: ICSC, accessed: 2019-09-04; Colorless, odorless gas. [Note: Shipped as a liquefied compressed gas. Solid form is utilized as dry ice.] source: NIOSH NPG, accessed: 2019-09-02
  • H2O – Water, oxidane source: wikipedia, accessed: 2019-09-27
    • Other names: Water (H2O) source: wikipedia, accessed: 2019-09-27, Hydrogen hydroxide (HH or HOH) source: wikipedia, accessed: 2019-09-27, Hydrogen oxide source: wikipedia, accessed: 2019-09-27
    • Appearance: White crystalline solid, almost colorless liquid with a hint of blue, colorless gas source: wikipedia, accessed: 2019-09-27